Interval timer



K. M. KlEL INTERVAL TIMER 3 Sheets-$heet 1 Filed Sept. 29, 1951 Feb. 2,- 1954 T K. M. KIEI. 2,667,736

INTERVAL TIMER Filed Sept. 29, 1951 a sheets-sheet 2 INVENTOR.

Feb. 2, 1954 KlEL 2,667,736

, INTERVAL TIMER Filed Sept. 29, 1951 s Sheets-Sheet 3' JNVENTOR. fixwrtfi M Kiel.

Patented Feb. 2, 1954 INTERVAL TIMER Kenneth M. Kiel, Ann Arbor, Mich., assignor to King-Seeley Corporation, Ann Arbor, Mich., a corporation of Michigan Application September 29, 1951, Serial No. 248,935

' of the signal means. including a bell afford one example of constructions in which it is desirable that the hammer 6 Claims. (Cl. s 21.13)

The present invention relates to an improved interval timer.

In interval timers, it is frequently desirable to move the signal actuating member to one position for actuating the signal and to return the signal actuating member to an at least partially withdrawn position immediately after actuation Interval timers of the type member whichstrikes the bell be returned to a position in which it is out of engagement with the bell.

It is an object of the present invention to provide an improved construction for interval timers where such return movement of the signal actuating member is desired. More particularly, it is an object of the present invention to provide such an improved construction which is simple in I design, reliable and eflicient in operation and economical of manufacture.

It is also an object of the present invention to provide an improved interval timer construction of the type including an escapement mechanism for returning the arbor to its zero position and the following specification, the appended claims and the accompanying drawings, wherein:

Figure 1 is an elevational view of a timer embodying the present invention, taken from one side thereof and showing the casing and bell removed;

Figure 2 is a sectional view of the construction illustrated in Figure 1, taken along the line A--1l thereof; and

Figure 3 is a an elevational view of the opposite side of the timer from that illustrated in Figure 1. Many of the features of construction of the timer illustrated in the accompanying drawings are of generally conventional design and only so much of the construction is illustrated and described in detail herein as is necessary for a full understanding of the features of the present invention. The interval timer to which the present invention relates, and which is shown in the accompanying drawings, is of the type in which the main arbor of the clockwork is provided with a manual control knob (not shown) and the construction and arrangement are such that when the arbor is rotated in one direction from a zero or starting position the signal actuator is cooked. The rate of return of the arbor to the starting position is controlled by the clock mechanism and the signal actuator is tripped upon return of the arbor to the starting position, thus operating a suitable signal.

Referring to the drawings, the present invention is shown incorporated in a timerhaving a clock mechanism carried by and between a pair of movement plates and I2. The clock mechanism includes a main arbor l4 suitably journaled in the movement plates and connected in the usual manner through a train of gears to a vergetype escapement comprising an escape wheel IS, a verge arm I8, and a balance wheel carried by a balance staff 22. The ends of the balance staff 22 are tapered and fitted into conical bearings 24 and 26 mounted, respectively, in the movement plates [0 and I2. A main spring 28 is mounted on the outer side of the movement plate I0, as best illustrated in Figures 1 and 2, and has its outer end anchored to an outwardly turned projection 30 on the movement plate 10 (see Figure 1) and has its inner end connected to the arbor M, as illustrated in Figures 1 and 2, by means of a spring anchor plate 32.

It will be appreciated that the spring 28 normally tends to rotate the arbor It in a counterclockwise direction as viewed in Figure l and in a clockwise direction as viewed in Figure 3, under the control of the escapement mechanism and associated gear train in the usual manner.

In the preferred embodiment illustrated in the drawings, the mechanism of the timer which operates the signal comprises a short stub shaft 34 secured to the movement plate l2 and on which is journaled a hammer bell crank 36, the shape of which is best illustrated in Figure 3. The bell crank 36 includes an outer arm portion 38 adapted to engage a suitable signal device which inv the preferred embodiment illustrated in the drawings is the bell indicated at 40, and an inner arm 42 having an outwardly turned projection 44 extending outwardly through an opening 46 provided in the movement plate I2. A spring 48 is mounted on the plate 12, as indicated at 50, and engages an outwardly turned projection 52 on the outer arm 38 of the signal actuator 36, which projection 52 extends outwardly through an opening '54 provided in the movement plate I2. The movement plate 12 is also provided with an outjection M on the hammer 36. '16, however, is provided with an inwardly turned projection l8'which engages a co-operating out- 'Wardly turned projection 86 on the latch plate nections with the .arbor illustrated in the copending application of Rex wardly turned projection 56 engaged by the spring 48 in the position of rest to which the signal actuator 36 comes after it is tripped.

The cooking and tripping mechanism comprises a latch 58 which is pivotally mounted on the movement plate I2 by a rivet 60 and is provided with a latching portion 62 adapted to move under the outwardly extending projection 44 on the signal actuator or hammer 36 to hold the hammer 36 in the cooked position. The latch 58 is urged in a counterclockwise direction, as viewed in Figure 3, by a spring 64, one end of which is mounted in the movement plate l2, as indicated at 66, and the other end of which engages an outwardly turned projectiontt on the latch arbor l4 and is drivingly connected thereto, as hereinafter described, for engaging the projection 44 of the hammer 36 and pivotally moving the hammer 36 in a counterclockwise direction, as viewed in Figure 3, to a position in which the spring 64 acting against the latch 58 may move the latching portion 62 of the latter into position to engage the projection ts on the hammer and hold the hammer in cocked position. For this purpose, the cam plate it is provided with a cam surface 12. The portion of the arbor 54 upon which the cam plate "it is mounted i5 provided with a pair of opposed parallel flats '54, best illustrated in Figure 2. The cam plate it is provided with a central opening, generally indicated at 16, receiving the portion of the arbor M having the flats "M. This opening it is adapted to provide a lost motion connection becounterclockwise direction, as viewed in Figure 3),-which is sufiicient to move the hammer so in a counterclockwise direction, as viewed in Figure 3, to its cocked position, in which the latching portion 52 of the latch .58 may be moved into engagement with the projection 44 by the spring 65. Also, the shape of the open- 9 ing 16 is such that upon rotation of the arbor E4 in the opposite direction, as during the return movement of the arbor to the starting or zero position under the control of the escapement mechanism, thecam plate it :is connected to'the arbor l4 and driven thereby with the cam surface i2 having a lesser effective height than during rotation of the arbor in the other di rection, so thatduring such return movement the cam plate 70 does not interfere with the .pro-

Thecam plate 58 -to-pivot the latch plate 58 in a clockwise direction, as viewed in Figure 3, and move the latching portion 62 out of engagement with the :projection =54, thereby tripping the hammer 36 -andpermitting the spring =36 to throw the outer arm portion 38 of the hammer 36 outwardly againstthe skirt of the bell fit.

The opening 76 in the cam plate 76 may be of any suitable shape providing the above mentioned two difierent connections between the arbor l4 and the cam plate It upon rotation of the arbor M in opposite directions. One suitable shape for the opening 76, providing such coni i at the flats 1.4 sis A cam plate i6 is mounted on the "means of which the hammer 36 is pivotally .mounted, so that the loading of the spring 82 produced by the engagement of the outer end of the spring 82 with the balance staff 22, when the hammer '36 is tripped, acts upon the hammer 36 through the mounting 8:1, to urge the hammer ,36 in a counterclockwise direction as viewed in Figure 3.

It will now be appreciated that, after a winding movement of the arbor I4, and a subsequent return movement of the arbor l4 and the cam plate '10 driven thereby, to a position in which the cam plate it through the engagement of the flange T8 thereon with the flange 86 of the latch, has moved the latch to the tripped position illustrated in Figure 3, the outer arm portion ,38 of the hammer 36 will be thrown outwardly by the action of the spring 48 so that the outer portion 38 moves from the cooked position indicated in broken lines at 86, outwardly to the position indicated in broken lines at 86 and'strikes the bell ii}. During this movement of the hammer 33 the spring 48 moves into engagement with the stop pro'ecticn 56 on the movement plate [2, thereby stopping the outward movement of the outer end of the spring 48 while the inertia imparted to the hammer to by the spring ii; causes it to continue outwardly to the position indicated at 88 in which it strikes the bell lfl. At this time it will be appreciated that the projection 62 has moved outwardly away from and outof engagement with the spring 33 and the spring 32 has moved into engagement with the stafi 22 and has been loaded by the continued movement of the hammer 36 outwardly against the bell $.0 This loading of the spring 22 acts through the mounting 34 to urge the hammer 36 in a counterclockwise direction, as viewed in Figure 3, to, a position in which the outwardly turned projection 52 on the hammer 36 engages the spring Q8. The spring 43 and the sp'ringBE are so proportioned that the hammer 36 comes to rest in the position illustrated in full lines in FigureB in which the spring 82 remains inengagement with the balance staff 22, providing a irictional engagement stopping the rotary movement thereof, and also continues to. act to hold the hammertfi in the position illustrated in Figure ,3.

While onlyone specificembodiment of the invention has been illustrated and described indetail herein, it will be readily appreciated by those skilled ;in the .art that numerous modifications tionto wind said main spring, scape mechanism for controlling the rateat whichsaid main spring drives said arbor, a signal actuating member movable between first and second positions, meanseifective uponmovement of said arbor in .saidone directionto a predetermined position for movingsaidrnember fromsaid first-position to said second position, and resilient means mounted on said member and operable upon said movement of said member to engage said mechanism to stop the movement of said arbor by said main spring and move said member from said second position toward said first position.

2. The combination as defined in claim 1, wherein said signal actuating member is mounted for pivotal movement, said first named means is effective to produce a moment efiecting pivotal movement of said member in one direction, and said last named means is effective upon pivotal movement of said member in said one direction to said second position, to produce a moment effecting pivotal movement from said second position and in the opposite direction.

3. The combination as defined in claim 1 including a bell disposed to be struck by said member upon the latter reaching said second position, and said resilient means being so disposed relative to and mounted on said member that as said member is moved to said second position said resilient means is loaded and acts to produce a moment effective to move said member out of engagement with said bell.

4. The combination as defined in claim 1, wherein said resilient means comprises an elongated cantilever spring having one end rigidly mounted on said signal actuating member and the other end adapted to engage said escape mechanism during said movement of said member to said second position.

5. In an interval timer, a main spring, an arbor disposed to be driven in one direction by said main spring and movable in the opposite direction to wind said main spring, escape mechanism for controlling the rate at which said main spring drives said arbor, a signal actuating member mounted for pivotal movement between first and second positions, means effective upon movement of said arbor in said one direction to a predetermined position for pivoting said member from said first position to said second position, said means including a spring element engaging said member, and a spring element mounted on said member and including a portion adapted to engage said escape mechanism during said movement of said member from said first position to said second position to stop the movement of said arbor by said main spring, said spring being loaded during said movement of said member and being efiective when said member reaches said second position to move said member from said second position toward said first position, the construction and arrangement of said escape mechanism, said member, and said spring elements, and the comparative loading of said spring elements being such that said member is moved from said second position to and comes to rest at a final position intermediate said first and second positions in which the moments exerted on said member by said spring elements are equal and said portion of said last named spring element remains in engagement with said escape mechanism.

6. The combination as defined in claim 5, wherein said second named spring element is an elongated cantilever spring having one end rigidly mounted on said member and the other end free when said member is in said first position and adapted to engage said escape mechanism to stop said arbor and load said second named spring element during said movement of said member to said second position.

KENNETH M. KIEL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,934,387 Tweedale Nov. 7, 1933 2,103,257 Hastings Dec. 28, 1937 2,150,633 Rhodes Mar. 14, 1939 2,258,474 Simmons Oct. 7, 1941 2,543,032 Laviana Feb. 27, 1951 2,562,378 Darnell July 31, 1951 

